PDF(Pubmed)
Abstract：
Animal songs can change within and between populations as the result of different evolutionary processes. When these processes include cultural transmission, the social learning of information or behaviours from conspecifics, songs can undergo rapid evolutions because cultural novelties can emerge more frequently than genetic mutations. Understanding these song variations over large temporal and spatial scales can provide insights into the patterns, drivers and limits of song evolution that can ultimately inform on the species\' capacity to adapt to rapidly changing acoustic environments. Here, we analysed changes in fin whale (Balaenoptera physalus) songs recorded over two decades across the central and eastern North Atlantic Ocean. We document a rapid replacement of song INIs (inter-note intervals) over just four singing seasons, that co-occurred with hybrid songs (with both INIs), and a clear geographic gradient in the occurrence of different song INIs during the transition period. We also found gradual changes in INIs and note frequencies over more than a decade with fin whales adopting song changes. These results provide evidence of vocal learning in fin whales and reveal patterns of song evolution that raise questions on the limits of song variation in this species.
摘要：
由于不同的进化过程，动物歌曲可以在种群内部和种群之间发生变化。当这些过程包括文化传播时，从特定物种中获得信息或行为的社会学习，歌曲可以经历快速发展，因为文化新奇比基因突变更频繁地出现。了解这些歌曲在大的时间和空间尺度上的变化可以提供对模式的见解，歌曲进化的驱动因素和限制，最终可以告知物种适应快速变化的声学环境的能力。这里,我们分析了北大西洋中部和东部二十年来记录的长鳍鲸（Balaenopteraphysalus）歌曲的变化。我们记录了仅在四个歌唱季节中快速替换歌曲INI（音符间隔），与混合歌曲（与两个INI）共同发生，以及在过渡期间不同歌曲INI的发生具有明显的地理梯度。我们还发现了十多年来INI和音符频率的逐渐变化，长须鲸采用了歌曲变化。这些结果为长须鲸的声音学习提供了证据，并揭示了歌曲进化的模式，这引起了对该物种歌曲变异极限的质疑。
